To: Ingo Molnar <mingo@redhat.com>
To: Peter Zijlstra <peterz@infradead.org>
To: Juri Lelli <juri.lelli@redhat.com>
To: Vincent Guittot <vincent.guittot@linaro.org>
To: Dietmar Eggemann <dietmar.eggemann@arm.com>
To: Steven Rostedt <rostedt@goodmis.org>
To: Ben Segall <bsegall@google.com>
To: Mel Gorman <mgorman@suse.de>
To: Valentin Schneider <vschneid@redhat.com>
Cc: linux-kernel@vger.kernel.org
Cc: Dhaval Giani <dhaval.giani@amd.com>
Cc: Gautham Shenoy <gautham.shenoy@amd.com>
Cc: K Prateek Nayak <kprateek.nayak@amd.com>
Signed-off-by: Dhaval Giani (AMD) <dhaval@gianis.ca>
---
 kernel/Kconfig.preempt     |  9 +++++++++
 kernel/sched/Makefile      |  1 +
 kernel/sched/debug.c       |  2 ++
 kernel/sched/eevdf-tests.c | 27 +++++++++++++++++++++++++++
 kernel/sched/sched.h       |  7 +++++++
 5 files changed, 46 insertions(+)

diff --git a/kernel/Kconfig.preempt b/kernel/Kconfig.preempt
index 54ea59ff8fbeb653b7084a78bd0d933076deaad5..96f47cf498aa10d7cbb375093e5533753ed7a414 100644
--- a/kernel/Kconfig.preempt
+++ b/kernel/Kconfig.preempt
@@ -176,3 +176,12 @@ config SCHED_CLASS_EXT
 	  For more information:
 	    Documentation/scheduler/sched-ext.rst
 	    https://github.com/sched-ext/scx
+
+config SCHED_EEVDF_TESTING
+	bool "EEVDF testing"
+	help
+	  This option is a debug option to test that your changes to the
+	  fair scheduling code do not break EEVDF invariants. There are
+	  controls exposted in debugfs to allow tests to be run. This has a
+	  performance impact, so do not enable unless you are a scheduler
+	  developer and know what you are doing.
diff --git a/kernel/sched/Makefile b/kernel/sched/Makefile
index 8ae86371ddcddf836172ee93ca34f2e91b4057a7..1a8416b8009ebf7cf38ac7b326f4b6472e62909a 100644
--- a/kernel/sched/Makefile
+++ b/kernel/sched/Makefile
@@ -37,3 +37,4 @@ obj-y += core.o
 obj-y += fair.o
 obj-y += build_policy.o
 obj-y += build_utility.o
+obj-y += eevdf-tests.o
diff --git a/kernel/sched/debug.c b/kernel/sched/debug.c
index 557246880a7e0839277df662703b7bfabeb3a497..e61acd5463145e4a54dcc816c1da774922ed0127 100644
--- a/kernel/sched/debug.c
+++ b/kernel/sched/debug.c
@@ -536,6 +536,8 @@ static __init int sched_init_debug(void)
 
 	debugfs_fair_server_init();
 
+	debugfs_eevdf_testing_init(debugfs_sched);
+
 	return 0;
 }
 late_initcall(sched_init_debug);
diff --git a/kernel/sched/eevdf-tests.c b/kernel/sched/eevdf-tests.c
new file mode 100644
index 0000000000000000000000000000000000000000..3bc016d3025733e53f586e30fcd31f650156d47e
--- /dev/null
+++ b/kernel/sched/eevdf-tests.c
@@ -0,0 +1,27 @@
+// SPDX-License-Identifier: GPL-2.0
+
+/*
+ * Copyright (C) 2025 Advanced Micro Devices, Inc
+ *
+ * Author: Dhaval Giani (AMD) <dhaval@gianis.ca>
+ *
+ * Basic functional tests for EEVDF - Invariants
+ *
+ * Use the debugfs triggers to run them
+ *
+ */
+
+#include <linux/debugfs.h>
+#include <linux/sched.h>
+
+#include "sched.h"
+
+#ifdef CONFIG_SCHED_EEVDF_TESTING
+
+static struct dentry *debugfs_eevdf_testing;
+void debugfs_eevdf_testing_init(struct dentry *debugfs_sched)
+{
+	debugfs_eevdf_testing = debugfs_create_dir("eevdf-testing", debugfs_sched);
+
+}
+#endif /* CONFIG_SCHED_EEVDF_TESTING */
diff --git a/kernel/sched/sched.h b/kernel/sched/sched.h
index c5a6a503eb6de3867ea25f13dca3660da2805ff8..09cefe2aa871bbd533a413c76026895e969a58e7 100644
--- a/kernel/sched/sched.h
+++ b/kernel/sched/sched.h
@@ -44,6 +44,7 @@
 #include <linux/lockdep.h>
 #include <linux/minmax.h>
 #include <linux/mm.h>
+#include <linux/mmu_context.h>
 #include <linux/module.h>
 #include <linux/mutex_api.h>
 #include <linux/plist.h>
@@ -3987,4 +3988,10 @@ void sched_enq_and_set_task(struct sched_enq_and_set_ctx *ctx);
 
 #include "ext.h"
 
+#ifdef CONFIG_SCHED_EEVDF_TESTING
+void debugfs_eevdf_testing_init(struct dentry *debugfs_sched);
+#else /* CONFIG_SCHED_EEVDF_TESTING */
+static inline void init_eevdf_testing_debugfs(struct dentry *debugfs_sched) {}
+#endif /* CONFIG_SCHED_EEVDF_TESTING */
+
 #endif /* _KERNEL_SCHED_SCHED_H */

-- 
2.49.0

Hi Dhaval,

kernel test robot noticed the following build errors:

[auto build test ERROR on c70fc32f44431bb30f9025ce753ba8be25acbba3]

url:    https://github.com/intel-lab-lkp/linux/commits/Dhaval-Giani-AMD/sched-fair-Introduce-a-new-debugfs-directory-for-EEVDF-tests/20250423-082221
base:   c70fc32f44431bb30f9025ce753ba8be25acbba3
patch link:    https://lore.kernel.org/r/20250422-b4-eevdf-tests-v1-post-v1-1-35d158254c72%40gianis.ca
patch subject: [PATCH 1/3] sched/fair: Introduce a new debugfs directory for EEVDF tests
config: x86_64-kexec (https://download.01.org/0day-ci/archive/20250507/202505071739.GJbmEQJp-lkp@intel.com/config)
compiler: clang version 20.1.2 (https://github.com/llvm/llvm-project 58df0ef89dd64126512e4ee27b4ac3fd8ddf6247)
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20250507/202505071739.GJbmEQJp-lkp@intel.com/reproduce)

If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <lkp@intel.com>
| Closes: https://lore.kernel.org/oe-kbuild-all/202505071739.GJbmEQJp-lkp@intel.com/

All errors (new ones prefixed by >>):

   In file included from kernel/sched/build_utility.c:71:
>> kernel/sched/debug.c:539:2: error: call to undeclared function 'debugfs_eevdf_testing_init'; ISO C99 and later do not support implicit function declarations [-Wimplicit-function-declaration]
     539 |         debugfs_eevdf_testing_init(debugfs_sched);
         |         ^
   1 error generated.


vim +/debugfs_eevdf_testing_init +539 kernel/sched/debug.c

   534	
   535		debugfs_create_file("debug", 0444, debugfs_sched, NULL, &sched_debug_fops);
   536	
   537		debugfs_fair_server_init();
   538	
 > 539		debugfs_eevdf_testing_init(debugfs_sched);
   540	
   541		return 0;
   542	}
   543	late_initcall(sched_init_debug);
   544	

-- 
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki